Fluid extracting piston press



p 1947- J. J. DE LA RozA, SR 2,427,446

FLUID EXTRACTING PISTON PRESS Filed March 31, 1945 I 4 INVENTOR. '5'e/mqa/ndae ma a.-

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particularly to a which mixtures of to extract the fluid from equippedwith cleaning apparatus have Patented Sept. 16, 1947- UNITED, STATESPA'rsrrr OFFICE 1 2,4am44s I Application March 31,3945, Serial No.586,016

, 4 Claims. (01. 100-50) This invention relates to improvements in afluid extracting fluid extracting device through fluids and solids arepassed the solid material. The press includes a pressure tube throughwhich the fluid-solid mixture is advanced by a reciprocatins piston. Thepressure fac of the piston is slotted apertures in which are advancedand retracted cleaning blades. The function of the slotted apertures isto serve as passageways for draining of! the extracted fluid while thecleaning blades prevent solids from clogging or forming an obstructionto passage of fluid through the slots.

The concept has to do primarily with th apparatus or the construction ofthe device and is therefore not limited to any particular use. In otherwords, the may be utilized in extracting fluids from fluidsolid mixturesof any kind, whether the solids be of vegetable, animal or mineralmatter com bined with' liquids of any kind such as water, hydrocarbons.or chemical solutions. In describing the invention the disclosure islimited to the extraction of water or liquor used in treatment ordigestion of vegetable fibers such as wood chips, bagasse, straw, bambooor other sources of cellulosic material.

In the separation of liquids from liquid-solid cellulosic mixturesdifficulties. are encountered due to the separation and entrainment ofgums, resinous and thickening susbtances which are carried off with theliquids and tend to obstruct the drains and passageways or ducts forremoving the separated liquids. Different types of been devised tomain.- tain the drain apertures and ducts clear and open with varyingdegrees of success. Where high pressures are necessary to satisfactorilyextract the liquids from the mixtures the problem of keeping dischargeopenings for the liquid tree of obstructions becomes a major concern inthe operation of the press or extracting device. In a copendingapplication, Serial No. 514,817, now Patent 2,398,135, issued April 9,1946, there is disclosed a press in which apertures in the piston faceor pressure plate constitute ducts which are circular in cross, sectionand which are cleaned by advancing and retarding cylindrical filterpins. The construction here suggested is to substitute for that structurparallel slotted openings or apertures in theiace of the piston in whichare reciprocated cleaning blades.

One of the objects of the invention therefore piston press and refersmore fluid extracting piston press upon the is to provide an improvedtype of fluid extracting piston press in which high pressures areimposed fluid-solid mixture to extract the fluid from the solids.

Another object is to provide a simple rugged type of construction whichwill withstand heavy pressures without clogging.

A further object is to provide a construction for effectively separatingfluids from a fluid-solid mixture wher there is a tendency for resinousand gummymaterials to be drained of! with the fluid.

Other and further objects 0! the invention will appear from thefollowing description.

In the accompanying drawings which form a art or the instantspecification and are to be read in conjunction therewith, and in whichlike reference numerals are used to indicat like parts in the variousviews,

Fig. l is a plan view ing the invention,

Fig. 2 is an enlarged sectional elevation of the device shown in Fig. 1,

Fig. 3 is a view taken along the line 2 in the directionof the arrows.

Fig. 4 is a view taken along the line 4-4 in Fig. 2 in the direction ofthe arrows.

Fig. 5 is a iragementary cross sectional view taken along the line 5-5of Fig. 2 in the direction of the arrows.

Referring to the drawings,'at III is shown a tubular passageway whichmay beoi any desired shape in cross section. This tube has an outlet onits right-hand end, and is either tapered or has positioned therein arestriction in the form of a valve or other'congesting device to limitthe size of the passageway. By compacting, congesting and increasing thedensity of the mixture pressure is imposed upon the congested mass andliquid extracted from 'the solids. Joined to the tube III at flanges IIis a cylinder I2 which has a top inlet port l3. Any suitable type ofconveyor or transporting duct such as a hopper or pipe is connected tothe inlet port l3 and serves of a piston pressembody- 3-3 in Fig.

to supply the mixture to be separated into the .cylinder.

1 therein. A plurality of bars I! form the pressure face of the piston.These bars are spaced apart by separators l6 shown in cross section inFig. 3

and are assembled together by bolts I1. and fit into the open end of thepiston upon the shoulder mentioned above. The bar assembly is held inplace on the shoulder by bolts l8 screwed into threaded aperturesdrilled axially of the piston walls Behind the bar assembly and withinthe piston housing is a circular plate i9 the outer diameter of which isslightly smaller than the bore of the housing whereby it is free toslide axially f the housing. On one side of this plate is a threadedaperture into which is screwed stop rod 20. The opposite side of theplate is slotted to receive a plurality of cleaning blades 2|. Thesecleaning blades are held in position in the of the plate by bolts 22.The free ends of the blades extend into and reciprocate, as will behereinafter explained, in the slots |5a between bars l5. Spacers i6which surround bolts l1 and are located between the bars l5 to form theslot ted openings move within the elongated apertures 2|a formed in eachof the blades as shown in Fig. 4. Extending through all but the upperbar l5 and adjacent the forward face of the piston are elongated ducts23 which form a continuous pas geway for draining extracted fluid to thehorizontal pipe 24 in the lowest bar. Fluid extracted with congestion orcompacting of the fluid-solid mixture passes through the horizontalslots in'the piston face between'bars I5 into the vertical duct 23. Fromduct 23 it passes through the lower horizontal duct 24 from which it isdischarged into the space between the bar assembly and plate IS. Agroove 25 extending longitudinally along the bottom of the inner wall ofthe piston permits the fluid to drain from this space and discharges itinto the flexible pipe 28 by means of which it is discharged from thepress. To assure a pressure-tight fit between the piston and cylinderadjacent the driven end of thepiston a flanged ring 2'! is bolted to thecylinder and holds in place a sealing ring or gasket 28 in the form of apacked gland between the inner face of the cylinder and outer peripheryof the piston housing.

The piston is reciprocated by rotation of shaft 29 which receives itsenergy from any suitable source of power not shown. on the end of theshaft is a crank 30 whose crank pin 3| bears in the end of yoke 32. Arms32a of the yoke bear in crosshead 33 bolted to the end of the piston.The arms of the yoke straddle stops 35 and 36.

As previously suggested, there is screwed into one side of plate I9 astop rod 20 whose function is to limit with the aid of stops 35 and 36the travel of cleaning blades 2| and plate IS. A gland 31 and stuflingbox in the end of the piston surrounding the rod prevents leakage.

In operation the fluid-solid mixture from which the fluid is to beextracted is introduced to the press through inlet I3. the piston thematerial is pressed forwardly (i. e., to the right) through tube l0toward the outlet and due either to the shape of the tube or arestriction placed in the tube in the form of a valve the material iscongested and compacted to a high density in the tube. Withreciprocation of the piston fluid is separated from the solids drainingthrough the slots in the face of the piston into vertical duct 23.

Cleaning of the slots between bars i5 is accomplished by reciprocationor sliding movement of the cleaning blades 2| in the slots. This. ismade possible by the relative differences in lengths of travel of thestroke of the piston and carrier 4 plate It upon which the cleaningblades are mounted. As the piston is advanced during its pressure strokebolts l'l slide spacer members l8 forward in slots 2|a of the blades andmove the blades forwardly to an advanced position, as shown in Fig. 2.The end of stop rod 20 extends through the rear piston wall and a holein stop 28. At its end between stops l5 and 86 is a cross pin 38.Abutment of this cross pin on stop 38. limits the forward movement ofplate l9 and blades 2|. Rearward movement of the plate and blades isarrested by abutment of the rod and cross pin on stop". In operationwhen the piston is retracted by action of the crank pin 80 from itsadvanced position shown in Fig. 2 clea ing blades 2| remain stationaryin the piston and travel with it during the initial stages of the returnstroke. When stop rod 20 moving with the piston abuts stop 35 furtherretraction of the blade carrier plate It! is halted and as the pistoncontinues its rearward stroke the blades are advanced in the slots untiltheir forward edges are flush with With the reciprocation of I V throughthe face of the piston or extend slightly therebeyond. When the bladesand'carrier plate'stop, continued rearward reciprocation of the pistonmoves bolts l1 and spacers I8 through slots 2: until they arrive attheir rearward ends. Thus, reciprocation of the piston from an advancedposition by crank II in a stroke whose length is determined by the throwof the crank causes the blades to travel with the piston until stoppedby abutment of rod 20 with stop 35. Then the movement of the cleaningblades within the slots is arrested and as the piston continues to moverearwardly the blades are advanced in their slots toward the face of thepiston as described. Slots 2 la through which bolts I! pass permitcontinued rearward movement of the piston after the blades have beenstopped.

When the direction of the piston is reversed on its forward or pressurestroke, the cleaning blades in their advanced position in the pistontravel with the piston until stopped by abutment of cross pin 38 withstop 36. The piston continues to advance but as the travel of the bladesis arrested they are again retracted in the slots of the piston to aposition shown in Figs. 2 and 4. Thus, movement 01' the cleaning bladesthrough the slots in the face of the piston is synchronized with thepistons stroke to retract the blades from the piston face during theforward pressure stroke and advance the blades during the rearwardstroke. Advancement of the' cleaning blades the slots removes any solidmaterial pressed into the slots during the pressure stroke or carriedinto the slots with the fluid. When pressures are employed or 1000pounds or upward during fluid extraction of the mass and when thematerial being extracted contains resinous and gummy materials theimportance of an efllcient cleaning mechanism is appreciated.

In the extraction of fluids from vegetable flbrous materials containingincrustants including waxes, resins, sugars and other substances readilyseparable from the fibers and drained with the fluids, it becomes of theutmost importance to keep the drains and channels through which theextracted fluids are removed open and free from accumulation of solids.

While the invention has been described in connection with its use in theproduction of pulp from vegetable fiber, it may as well be used in theextraction of fluids from any substances where it is desired to removeliquids from solids.

From the foregoing it will be seen that the in- As many possibleembodiments may be made of the invention it is understood that allmatter herein set forth or shown in the drawings is to be interpreted asillustrative and not in a limiting sense;

Having thus described my invention, I claim:

1. A fluid extracting piston press for separating fluids fromfluid-solid mixtures comprising a pressure tube, a piston reciprocatingtherein and means for reciprocating the piston, inlet and outlet portsin the tube for introducing material to be extracted and for dischargingextracted materials, slotted apertures in the face of the piston, adrain connected to said apertures, and cleaning blades slidable in theslotted apertures adapted to clean the slots of the piston with eachreciprocation thereof and permit free passage of the extracted fluidthrough the slots and drain.

2. A piston press as in claim 1 having a reciprocating blade assembly onwhich the cleaning blades are mounted, said blade assembly synchronizedwith the reciprocation of the piston to retract the cleaning blades fromthe face of the piston at the forward or pressure end and advance theblades at the rearward stroke of the piston.

3. A piston press as in claim 1 having a reciprocating blade assembly onwhich the cleaning blades are mounted, said blade assembly recipnestedin an opposed direction to the direction or the piston strokes and meansfor governing the length of the strokes of the blade assembly.

4. A piston press for separating fluids from fluid-solid mixturescomprising a pressure tube having inlet and outlet ports, a pistonreciprocable therein and means for reciprocating the piston, a pluralityof spaced apart elements in the race of the piston, a drain connectingthe slots between said elements, a blade assembly including a platepositioned rearwardly of said elements and cleaning blades mounted onthe plate so they extend forwardly therefrom into said slots, and meansdriven from the piston reciprocating means for advancing and retractingthe blade assembly in opposed directions to the travel of the piston.

JOAQUIN J. on LA ROZA, Sn.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

